Select the most appropriate option to fill in the blank.
Virtual worlds are recently new phenomena in that they _________ people to meet and socially interact with others in a variety of online environments.

Correct option is D

The correct option to fill in the blank is (d) enable.
Virtual worlds allow people to meet and interact socially, so "enable" fits best.
Meanings of other options:
• Forbid: to prohibit.
• Bring: to cause to come along with.
• Choose: to select from a number of possibilities.