Choice A is correct, If $2.5$ ounces of chocolate are needed for each muffin, then the number of ounces of chocolate needed to make $48$ muffins is $48$ x $2.5 = 120$ ounces. Since $1 pound = 16 ounces$, the number of pounds that is equivalent to 120 ounces is $\dfrac{120}{16} = 7.5$ pounds. Therefore, $7.5$ pounds of chocolate are needed to make the $48$

Choice B is incorrect. If $10$ pounds of chocolate were needed to make $48$ muffins, then the total number of ounces of chocolate needed would be $10$ x $16$ $= 160$ ounces. The number of ounces of chocolate per muffin would then be $\dfrac{160}{48} = 3.33$ ounces per muffin, not $2.5$ ounces per muffin. Choices C and D are also incorrect. Following the same procedures as used to test choice B gives $16.8$ ounces per muffin for choice C and $40$ ounces per muffin for choice D, not $25$ ounces per muffin. Therefore, $50.5$ and $120$ pounds cannot be the number of pounds needed to make $48$ signature chocolate muffins.