In this task, find the most appropriate number to replace the blank (indicated with _ ) and express it in words.

Q: Many Asian countries deny entry to travelers whose passports are valid for less than _ months.

A: six
****
Q: Carbon comes in _ kinds- dust, coconut shell or granulated.

A: three
****
Q: Orchids fall into _ categories, species and hybrids.

A:
two
****