Final answer:
The tropical climate in most of the islands of Oceania can be attributed to their location near or along the equator, resulting in higher average temperatures, high humidity, and regular heavy rains.
Step-by-step explanation:
The majority of the islands in Oceania exhibit a tropical climate mainly because these islands are situated near or along the equator. Being positioned near the equator implies intense sunlight year-round, leading to higher average temperatures and fostering a tropical climate. The position of these islands contributes significantly to their warmer weather patterns, high humidity, and regular heavy rains, which are all characteristics of a tropical climate. Hence, option C: 'They are located along the equator,' correctly explains why most of the islands in Oceania have a tropical climate.
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