Given are the statements about primary and secondary batteries. Identify the correct statement(s).
(I) Mercury cell is suitable for low current devices like hearing aids, watches, etc.

(II) Leclanche cell is used commonly in wet laboratories and schools.

(III) Lead storage battery is commonly used in automobiles and inverters.

Correct option is B

Correct Answer: (b) I, II and III
Explanation:
All three statements are considered correct as per the answer key:
· (I) Mercury cell is suitable for low-current devices True — Mercury cells give a constant voltage and are used in watches, hearing aids, calculators, etc.
· (II) Leclanché cell is used commonly in wet laboratories and schools Accepted as correct in the key — The original Leclanché cell (a wet cell) was historically used for laboratory demonstrations and school experiments to explain battery chemistry.
· (III) Lead storage battery is used in automobiles and inverters True — It is a secondary (rechargeable) battery, widely used in cars, bikes, trucks, inverters, UPS systems.
Information Booster:
· Primary batteries: Mercury cell, dry cell — not rechargeable.
· Secondary batteries: Lead-acid battery, Ni–Cd, Li-ion — rechargeable.
· Leclanché cell exists in two forms:
· Wet Leclanché cell (used historically in labs)
· Dry cell (the common battery used in torches, remotes).