Answer:
A. Oceans have an effect on coastal climate
Explanation:
There is no evidence on the map to support any of the offered statements. Using wild speculation, we might conclude ...
A. Oceans have an effect on coastal climate
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There is no information on the map to allow us to gauge city size or elevation, eliminating choices C and D.
We note that the city farthest north (Minneapolis) has the greatest difference between high and low temperatures, so we can rule out choice B.
Something has an effect on the climate of San Francisco, which has the least difference between high and low temperatures. We note that it is near the Pacific Ocean, which lends some credence to the speculation that the ocean has an effect. Both Wichita and Minneapolis are farther inland, and both have a less mild climate than Dallas or San Francisco.
There is obvious correlation between distance from the coast and the city's temperature extremes. However, correlation is not evidence of causation. Having ruled out choices B, C, D, we are left with choice A. This map provides no evidence one way or the other for that one.