Questions

Metal Aluminium is present in chocolate wrappers.

The water rise in a capillary tube dipped in water is such that the weight of water in the tube above the surface of water in the vessel is equal to (balances) the upward force due to surface tension. So it is clear that if the the bore (radius) to the tube is decreased, the height of the water column in it must be greater.  So, (a) is correct.

Edward Thorndike (1874 - 1949) is famous in psychology for his work on learning theory that lead to the development of operant conditioning within behaviorism.

Thorndike (1898) studied learning in animals (usually cats). He devised a classic experiment in which he used a puzzle box to empirically test the laws of learning.

Ethylene is used for Artificial Ripening of Green Fruit.

• Calcium carbide is also used in some countries for artificially ripening fruit. When calcium carbide comes in contact with moisture, it produces acetylene gas, which is quite similar in its effects to the natural ripening agent, ethylene