Which equation is incorrect?

answer:   a. (abc/2)² = (a²b²c²/4)

step-by-step explanation: you have to follow this rule, every exponent into the equation must be elevated 3 times.

for this case will be applicable the exponent summary,

(abc/2)²

so if you apply this equation value by value you will get the following

a * a = a²

b * b = b²

c * c = c²

2 * 2 = 4

then we get this equation (a²b²c²/4)

if you this rule with the rest of equation, you will find wrong results, because are bad performed, because of that the correct answer is the a