Question

(a)
(1) who doesnt enjoy flying a kite? (2) when you seen people in your community flying kites on a windy day, you might think that kites are just for fun. (3) kites have been flown in countries around the world and for centuries, by young and old alike. (4) however, kite flying, it may surprise you to know, have been responsible for a number of scientific discoveries.
(b)
(5) in 1752, benjamin franklin used a kite to prove the presence of electricity in storm clouds. (6) he did it by flying a kite during a thunder - storm with a brass key attached to the end. (7) the story goes that, when lightning struck the kite line and traveled down to the key, their was a spark of electricity.
(c)
(8) kites also played a role in learning about the weather. (9) in 1749, alexander wilson of scotland became the first scientist to send a thermometer aloft in a kite. (10) starting in the 1890s, kites held meteorological instruments that also measured humidity and wind speed. (11) they measured barometric pressure too.
(d)
(12) kites were an early form of aircraft: (13) the wright brothers, inventors of the first plane, experimented with kites. (14) alexander graham bell, the physicist and inventor, used kites to learn about problems of airplane construction.
(e)
(15) so the next time you see some neighborhood children flying kites, just think. (16) you may be watching budding young scientists.

1. sentence 4: however, kite flying, it may surprise you to know, have been responsible for a number of scientific discoveries.

which is the best way to write the underlined portion of the sentence?
o a would be
o b has been
o c were
o d are

Explanation:

The subject "kite flying" is singular. Present - perfect tense "has been" is appropriate here as it indicates an action that started in the past and has a connection to the present (kite - flying has had an impact on scientific discoveries over time).

Answer:

B. has been