Many insects may consume pollen or the nectar without bringing about pollination. Such floral visitors are referred to as pollen/nectar robbers. Which amongst the following is an example of nectar robber?

• A

  Species of moth on Yucca plant

• B

  Fig wasp on Ficus plant

• C

  Queen of Bombus affinis on Aquilegia spurs

• D

  Bees on sunflower.