This has a great number of... a) cowb)sheepc)oxd)goose с обьснением почему так​

sheep  

a great number of-"большое количество" (требуется существительное во множественном числе.Sheep -имеет одинаковую форму в ед. и во мн. числе.Все другие существительные во мн. числе выглядят так:cows,oxen,geese.

Объяснение:

This text is about a biologist and conservationist Roger Payne. He discovered that whales sing and their songs can be heard across entire oceans.

Before he studied whales he had become an expert in animal acoustics. In 1967 Roger went to Bermuda where he met Frank Watlington. Frank told Roger about strange sounds that he had heard underwater. Frank thought the noises were coming from whales.

After that Payne and his colleague Scott McVay found out that the sounds were whales' songs which could travel across entire oceans. It happened at the time when hunters killed thousands of whales.  Roger Payne released a recording of whale songs and it helped to start the 'Save the Whales' movement. In 1986 commercial whaling was banned.

Payne still is busy studying and protecting whales.

Hey, Michael! Haven't heard from you for ages! How have you been? What's new? I'm having my exams at the end of this semester and I'm going to take Math, Russian because they are compulsory. I also have chosen to take chemistry and biology because I think they are really important for me due to the fact that I want to become a doctor. And I also consider them very captivating and interesting as they give us so much to learn about us, human beings. I think nothing could be more mysterious than us, people, that's why I chose to study them hard. I actually want to study languages more as they are crucial too but unfortunately I do not simply have the time for that. That's a pity! What subject do you like to study, Mike? I am really looking forward to seeing you who's summer! Hope we'll both do well in our exams! Sincerely, Ann