Joseph is making kebabs. He wants each kebab to have 3 pieces of meat and 4 pieces of vegetables. Which of the following could Joseph use to make kebabs without any leftovers? Choose 3 answers: A 18 pieces of meat and 30 pieces of vegetables B 20 pieces of meat and 32 pieces of vegetables [c 30 pieces of meat and 40 pieces of vegetables D 45 pieces of meat and 60 pieces of vegetables

Step 1 ：First, we need to find the options where the number of pieces of meat and vegetables can be divided evenly by 3 and 4 respectively, as each kebab requires 3 pieces of meat and 4 pieces of vegetables.

Step 2 ：Let's go through the options one by one:

Step 3 ：Option A: 18 pieces of meat and 30 pieces of vegetables. \(\frac{18}{3} = 6\) and \(\frac{30}{4} = 7.5\). So, this option would leave leftovers.

Step 4 ：Option B: 20 pieces of meat and 32 pieces of vegetables. \(\frac{20}{3} \approx 6.67\) and \(\frac{32}{4} = 8\). So, this option would also leave leftovers.

Step 5 ：Option C: 30 pieces of meat and 40 pieces of vegetables. \(\frac{30}{3} = 10\) and \(\frac{40}{4} = 10\). So, this option would not leave any leftovers.

Step 6 ：Option D: 45 pieces of meat and 60 pieces of vegetables. \(\frac{45}{3} = 15\) and \(\frac{60}{4} = 15\). So, this option would not leave any leftovers.

Step 7 ：So, the correct answers are options C and D, which are \(\boxed{C}\) and \(\boxed{D}\).