Option 1 states that both statements are individually true and that Statement II is the correct explanation of Statement I. Let`s examine each statement to understand if this option is the correct answer.

Statement I states that the Grand Banks are one of the major fishing grounds of the world due to the presence of a vast continental shelf. This statement is true. The Grand Banks, located off the coast of Newfoundland in Canada, are known for their rich fishing grounds. The presence of a vast continental shelf provides a suitable habitat for various fish species, making it an important fishing area.

Statement II states that planktons grow in shallow waters. This statement is also true. Planktons are microscopic organisms that form the base of the marine food chain. They require sunlight for photosynthesis, and shallow waters receive more sunlight compared to deeper waters. Therefore, shallow waters are conducive to plankton growth.

In this case, Statement I (Grand Banks as major fishing grounds) is supported by Statement II (planktons grow in shallow waters). Therefore, Option 1 is the correct answer. Both statements are true, and Statement II offers an accurate explanation for Statement I.