Choose A, B, C, or D to indicate the sentence which is the most correct.

When / their mother / came home / 10 o'clock last night, / they / not study; / they / chat.

When I was young, walking barefoot was a common experience at school.

When I was young, walking barefoot is a common experience at school.

When I am young, walking barefoot was a common experience at school.

When I am young, walking barefoot is a common experience at school.

In old days, our school schedule consists of morning lessons only.

In the old days, our school schedule consisted of morning lessons only.

In the old days, our school schedule consisted about morning lessons only.

In the old days, our school schedule would consisted in morning lessons only.

No other religious building in the world is as large as Angkor Wat.

All other religious monuments in the world are larger than Angkor Wat.

No other religious monument in the world is as large as Angkor Wat.

No other religious building in the world is larger than Angkor Wat.

Windsor Castle, which was built a thousand years ago, is the home for about 40 English kings and queens.

Windsor Castle, was built a thousand years before, but it is the home for about 40 English kings and queens.

Windsor Castle, was built a thousand years ago, so it is the home for about 40 English kings and queens.

Windsor Castle, was built in a thousand years, and is the home for about 40 English kings and queens.

Dinh Bang Communal house is a 300-year-old communal house, that were built for 36 years.

Dinh Bang Communal house, which is a 300-year-old communal house, was built for 36 years.

Dinh Bang Communal house, what is a 300-year-old communal house, was built for 36 years.

Dinh Bang Communal house, was built for 36 years, is a 300-year-old communal house.

In our childhood, the three-month summer holiday is the highlight for the year.

In our childhood, the three-month summer holiday was the highlight at the year.

In our childhood, the three-month summer holiday is the highlight of the year.

In our childhood, the three-month summer holiday was the highlight of the year.

I was making a presentation when the microphone stopped working last week.

I made a presentation when the microphone was stopped working last week.

I am making a presentation when the microphone stopped working last week.

I was making a presentation when the microphone stop working last week.