Correct Answer: (b) Cloud seeding involves use of chemicals that target rain-bearing clouds above a catchment area such as a river, reservoir or a lake
Solution:'Catchment', 'river' & 'lake' are the words that start with a consonant sound & we always use the indefinite article 'a' before the words starting with a consonant sound. Hence, 'Cloud seeding involves use of chemicals that target rain-bearing clouds above a catchment area such as a river, reservoir or a lake' is the most appropriate answer.