Correct Answer: He killed his wife.

Solution : The correct choice is the third option.

Active voice is the voice where the subject performs the action. When converting a sentence from the passive voice to the active voice, the subject performs the action rather than the action received by the subject.

The structure of the active voice in the case of the simple past tense is: "Singular subject + past form of the verb + object."

Therefore, the sentence in the active voice is: "He killed his wife."

Correct Answer: a widely remit and a wise legacy.

Solution : The correct choice is the second option.

The error lies in the use of "widely", which should be replaced with "wide". 

"Wide" functions as an adjective that helps modify the noun "remit", which means an area of responsibility and authority. This helps convey the intended meaning that the Supreme Court has a broad and comprehensive scope of authority.

Therefore, the correct sentence is: A key institution is the judiciary, especially the Supreme Court, with a wide remit and a wise legacy.

Correct Answer: PORQ

Solution : The third option is the correct answer.

It begins by introducing the subject, (P). Subsequently, it adds details about the manner in which this activity is conducted, (O). Moving on, the sentence highlights one of the positive outcomes, (R). Finally, it expands on the health benefits, (Q).

Therefore, the correct answer is: Engaging in physical activity on a regular basis can improve cardiovascular health, reduce the risk of chronic diseases, and boost mental health. 

Correct Answer: $50$%

Solution : Let the principal be Rs. $x$.
Rate of interest = R%
Time = 3 years
Amount = $3\frac{3}{8}=3.375x$
We know, $\text{Total amount}=\text{Principal}×(1+\frac{\text{Rate}}{100})^{\text{Time}}$
$⇒3.375x = x(1 + \frac{R}{100})^{3}$
$⇒3.375 =(1 + \frac{R}{100})^{3}$
$⇒(1 + \frac{R}{100})^{3} = (1.5)^{3}$
$⇒(1 + \frac{R}{100}) = (1.5)$
$⇒\frac{R}{100}=0.5$
$\therefore R=50$%
Hence, the correct answer is $50$%.

Correct Answer: Non-profit MFIs

Solution : The answer is Non-profit MFIs.

In general, microfinance institutions in India fall into three categories: mutual benefit, for-profit, and not-for-profit. Only non-banking financial businesses, or NBFC-MFIs, which are for-profit microfinance institutions, are subject to Reserve Bank of India (RBI) regulation.

Correct Answer: Believable

Solution : The correct choice is the fourth option.

The adjective "incredible" means something unbelievable, extraordinary, or difficult to believe due to being extraordinary or improbable.

Its antonym is the adjective "believable". It refers to something believable, which means it can be accepted as true or credible.

The meanings of the other options are as follows:

The adjective strained describes something that is stretched or forced, often indicating difficulty or tension.

The adjective far-fetched describes something unlikely and often requires a creative leap of the mind.

The adjective implausible describes something that is not likely to happen or be true; it doesn't seem reasonable or probable.

Therefore, the correct antonym is believable.

Correct Answer: France

Solution : The correct option is France.

The Summer Olympic Games are a major international sporting event held every four years, with sports competitions involving athletes around the world. It will be held in 2024 in the capital city of Paris, France. The Summer Olympics feature a wide range of sports, including athletics, swimming, gymnastics and various team sports.

Correct Answer: Goa to Mumbai

Solution : The correct answer is Goa to Mumbai.

The Konkan, also known as Aparanta, is a coastal plain in western India that spans over the Western Ghats to the east and the Arabian Sea to the west. The Konkan Coast is the region that includes Goa's and Maharashtra's coastlines.

Correct Answer: Bushfire have created havoc

Solution : The first option is correct.

In this part of the sentence, bushfire is a singular noun, but have is a plural verb, so they don't agree in number.

According to the subject-verb agreement, if the subject is plural, the verb must be plural. Conversely, if the subject is singular, the verb must be singular.

Therefore, the correct sentence will be: Bushfires have created havoc and exacerbated the conditions of animals in the forest.

Correct Answer: Nine times

Solution : The correct answer is Nine times.

Any conducting coil's ability to resist changes in current flow is known as self-inductance. A solenoid's self-inductance increases by nine times when the number of turns in the coil triples without any change in the coil's length. The coil's self-inductance is directly proportional to the square of the number of turns. The formula for the self-inductance (L) of a coil is L= μ⋅N2⋅A​/ l.