听下面一段独白，回答以下小题。
【小题1】What causes popcorn kernels to turn into fluffy popcorn?

A．Mixing with butter

B．Heat and pressure

C．Freezing

【小题2】What happens to the water inside a popcorn kernel when it’s heated?

A．It evaporates

B．It turns into steam

C．It freezes

【小题3】What is the outcome of the pressure created inside a popcorn kernel?

A．It shrinks

B．It explodes

C．It becomes soft

【小题4】What is the comparison made in the speech regarding popping popcorn?

A．A mini-explosion of science

B．A burst of flavor

C．A magic trick

【小题5】What is the main idea behind the explanation of popcorn popping?

A．Mixing ingredients

B．Heat and pressure causing explosion

C．Freezing the kernels

【小题6】What happens to the popcorn kernel as a result of the pressure build-up?

A．It deflates

B．It turns into a liquid

C．It bursts open

【小题7】What term is used to describe the transformation of a popcorn kernel into fluffy popcorn?

A．Popping

B．Melting

C．Dissolving