Which one of the following crops is often cross-pollinated?

Answer: Option B

Groundnut crop is often cross-pollinated.
In some crop plants, cross-pollination often exceeds 5 percent and may reach 30 percent. Such species are generally known as often cross-pollinated species.
About 1.0 to 3.9% of cross-pollination has been reported to take place naturally in groundnut. Several bee species are the pollinators in the out-crossing of groundnuts.