Read the following passage and mark the letter A, B, C, or D on your answer sheet to indicate the correct word or phrase that best fits each of the numbered blanks from 1 to 5.

Drone racing is an exciting new sport, that has become popular faster than (1)______ other sport before it. Pilots steer small and lightweight, but high-powered drones along courses with obstacles. They fly through gates and around flags at speeds of over a hundred miles an hour.

They control the drones using VR-like headgear. Every drone has a camera (2)______ to it so that spectators can also view flights either on a big screen or with special headgear.

The races take place either outdoors - in big stadiums, or indoors in old warehouses and sports arenas. (3)______ are short because the battery time of drones is limited.

(4)______ drone racing started only a few years ago there are already international competitions that take place all over the world. In professional leagues, drone pilots compete for thousands of dollars. In March, the World Drone Prix was staged in Dubai. A 16-year old British teenager not only one the race but also received a prize money of 250 000 dollars.

Television and other media have become aware of drone racing. ESPN, an Amercian sports channel, will be broadcasting international drone races starting this August. Races are also recorded and uploaded to YouTube and other video platforms (5)______ they can be viewed over and over again.

Điền ô số 4

A. However 

B. Moreover 

C. Although 

D. Because