Question

while researching a topic, a student has taken the following notes:

• a supercontinent is a single landmass made up of most or all of earth’s continents.
• over time, continents merge together to form supercontinents, which then break apart.
• this process is believed to take hundreds of millions of years and is known as the supercontinent cycle.
• vaalbara was a supercontinent that formed about 3.6 billion years ago.
• euramerica was a supercontinent that formed about 300 million years ago.

the student wants to emphasize the order in which the supercontinents were formed. which choice most effectively uses relevant information from the notes to accomplish this goal?

a. vaalbara and euramerica were both supercontinents, single landmasses made up of most or all of earth’s continents.
b. the supercontinent euramerica formed long after the supercontinent vaalbara.
c. forming and breaking apart over hundreds of millions of years, supercontinents are made up of most or all of earth’s continents.
d. vaalbara formed about 3.6 billion years ago but eventually broke apart.

Explanation:

To emphasize the formation order, we compare the formation times. Vaalbara formed ~3.6 billion years ago, Euramerica ~300 million years ago. Option B states Euramerica formed long after Vaalbara, using their formation times (from notes) to show order. Other options don't focus on order.

Answer:

B. The supercontinent Euramerica formed long after the supercontinent Vaalbara.