Question

Which of the following numbers have 4 different prime factors?

• A. 100
• B. 120
• C. 210
• D. 32

Answer 1

The correct option is C 210

$100=2\times 2\times 5\times 5120=2\times 2\times 3\times 5210=2\times 3\times 5\times 732=2\times 2\times 2\times 2\times 2$
210 has four different prime factors.