Correct Answer: antidote

Solution : The correct choice is the fourth option.
An antidote is a substance that can counteract or neutralise the effects of a poison or toxin. In the context of a venomous snakebite, an antidote is the most appropriate term.

The meanings of the other options are as follows:

• Antiseptic: A substance that prevents the growth of disease-causing microorganisms.
• Anti-serum: A serum containing antibodies that may provide immunity to certain toxins or diseases.
• Remedy: A general term for a treatment or solution.

Therefore, the correct answer is antidote.

Correct Answer: for

Solution : The first option is the correct choice.

The correct preposition to use in this context is "for", as it is used when someone starts a journey to reach a particular destination or to perform a certain action.

Therefore, the complete sentence is: Hearing of her grandmother's illness, she at once started for Mumbai.

Correct Answer: was lifting

Solution : The correct answer is the fourth option.

Explanation: In the given sentence it indicates that the action of pulling a muscle occurred while lifting weights. So, the past continuous tense (was lifting) is appropriate for expressing the ongoing action at the time the muscle was pulled.

Therefore, the correct sentence would be: The young man was lifting weights at the gym when he pulled a muscle.

Correct Answer: chess

Solution : The correct answer is chess

Viswanathan Anand, Pentala Harikrishna, and Vidit Gujrathi are renowned Indian chess grandmasters. Anand, hailing from Chennai, is a former World Chess Champion and a global chess legend. Harikrishna and Gujrathi, both highly skilled players, contribute significantly to India's strong presence in international chess, showcasing strategic brilliance and skill on the global chess stage.

Correct Answer: 116

Solution : Given:
50 A 86 C 40 D 10 B 5 = ?

On interchanging the mathematical signs, we get –
= 50 + 86 – 40 ÷ 10 × 5
= 50 + 86 – 4 × 5
= 136 – 20
= 116

Hence, the third option is correct.

Correct Answer: Kohlrausch

Solution : The correct answer is Kohlrausch.

According to Kohlrausch's law of independent ion migration, an electrolyte's limiting molar conductivity can be expressed as the total of the individual contributions made by its cations and anions. Because there are fewer ions available for conduction, a solution's conductivity decreases with dilution.

Correct Answer: Mixture of rewards and punishments

Solution : The first option is correct.

Explanation: The idiom carrot and stick approach is a metaphorical expression derived from the idea of motivating a donkey to move forward by dangling a carrot in front of it and simultaneously threatening with a stick from behind. Grammatically, it is used to describe a strategy that combines rewards and punishments to encourage desired behaviour.

Therefore, the correct meaning of the idiom is: "Mixture of rewards and punishments".

Correct Answer: No substitution required

Solution : The correct choice is the second option.

The original sentence, "He and his father take a ride every morning to the top of the hill", is grammatically correct. It describes the regular action of both a person and their father riding to the top of the hill every morning.

Therefore, there is no substitution required.

Correct Answer: Sparrow

Solution : Given:
Eagle, Ostrich, Kiwi
All three are types of birds.

Let's check each option –
First option: Unicorn; The Unicorn comes under the category of animals.
Second option: Bat; The Bat comes under the category of a flying mammal.
Third option: Sparrow; The sparrow comes under the category of birds.
Fourth option: Shark; The shark comes under the category of fish.

So, the sparrow comes under the category of the given words. Hence, the third option is correct.

Correct Answer: Shwetha

Solution : Given:
(I) Six students are sitting around a circular table facing the centre. Salman is an immediate neighbour of both Kiran and Shwetha.

(II) Bala is sitting second right to Salman. Shwetha is sitting third to the left of Bala. Akshay is an immediate neighbour of both Bala and Nishitha. 

So, Shwetha is the immediate neighbour of Nishitha and Salman. Hence, the third option is correct.