What happened to the ancient peoples of the indus valley?
a. they migrated to greece and rome during the gupta period.
b. they were wiped out by a tsunami during the 4th century.
c. they were annialated by the guptas as they expanded their territories.
d. they disappeared as though into thin air, and the cause remains unknown. select the best answer from the choices provided a b c d?

d. they disappeared as though into thin air, and the cause remains unknown.

The ancient peoples of the Indus Valley, also known as Harappans, disappeared during the later half of the 2nd millennium BCE. This was around a thousand years before the beginning of the Gupta period.

The cause of their disappearance is a matter of debate. Bodies from around that time show more signs of violence and disease. Some theories that have been proposed are an Aryan invasion, climate change, droughts and earthquakes. However, the cause is still unknown.

d. i assume the underlined word is "role." reformat if it isn't.

explanation:

role is closest to part because when replacing words, "playing a vital decision," "playing a vital activity," and "playing a vital dollar" don't make logical sense. the only meaningful choice is "playing a vital part."

this fits one of merriam-webster's definitions of role: "a function or part performed especially in a particular operation or process."