Which is a mixed number? a. $\frac{3}{4}$ c. $3 \frac{1}{2}$ b. $\frac{12}{5}$ d. 5 The answer is choose your answer...

Step 1 ：A mixed number is a whole number and a proper fraction combined into one 'mixed' number.

Step 2 ：Looking at the options, option a is a proper fraction, option b is an improper fraction, option d is a whole number.

Step 3 ：Option c is a mixed number because it has a whole number (3) and a proper fraction (1/2).

Step 4 ：So, the answer should be option c.

Step 5 ：Final Answer: The mixed number is \(\boxed{c. 3 \frac{1}{2}}\).