Answer: B

Since x, y, and z are positive, each of the exponents must be at least one. We want the value of p to be as small as possible, so the power of 2 should be as large as possible, and the power of 5 should be as small as possible. For instance, y and z cannot be smaller than 1, so if y = 1 and z= 1, that means x = 4:
(2^4)(3^1)(5^1)
= 16(3)(5)
= 240, choice (B).
Any change that would make the powers of 3 and 5 bigger at the expense of making the power of 2 smaller would generate a larger value of p.