What is the following key word used for? later choices: sequence adding an idea explanation or illustration emphasis and purpose time repetition and summary

The key word "later" is used to indicate sequence.

Explanation: "Later" is a signal word, which means that "later" is capable of establishing a relationship between ideas that are presented in one or more sentences. The type of relationship that this key word can establish is "sequence", which consists in presenting events in a specific order. In that way, "later" can be used to indicate that an event took place before another one.  

"throngs rushed to the coastal area near the airport from which the plane had taken off, overloaded with relief supplies clemente wanted to make sure reached the victims of an earthquake in nicaragua."