Answer: 24/25 (choice B)
This is because cosine of an angle is the ratio of the adjacent and hypotenuse
So,
cos(angle) = adjacent/hypotenuse
cos(a) = 24/25
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Extra info:
Something like 7/25 would be for the sin(a) value, and 7/24 is tan(a). The reciprocal of 7/24 leads to 24/7, which is the value of cot(a).
