The chief fishing grounds of the world occur where cold and warm currents meet. This is because.
1. cold currents are rich in nitrates and phosphates which feed plankton.
2. Such areas cause the water to become well-aerated.
3. the warm current brings the right temperature for marine life.
(a) 1 only (b) 2 only (c) 1, and 2 (d) 1, 2, and 3
