Answer:
A.16km by 8km
Step-by-step explanation:
Halley's comet is the most famous comet and it is visible to the naked eye from the Earth every 75 or 76 years. The last time it appeared was 1986 and it was studied with information obtained from the observations about the nucleus, coma and tail. It was determined that the nucleus is approximately 16 k by 8 km. It is expected that it will be seen again in 2061.