Question

in 1990, california native and researcher ellen ochoa left her position as chief of the intelligent systems technology branch at a nasa research center ______ the space agency’s astronaut training program. which choice completes the text so that it conforms to the conventions of standard english? choose 1 answer: a to join b is joining c joined d joins

Explanation:

The sentence needs an infinitive phrase to show the purpose of Ellen Ochoa leaving her position. The infinitive "to join" correctly expresses the intended action and follows Standard English conventions for indicating purpose after a main action (left her position). The other options create grammatical errors: "is joining" creates a run-on, "joined" and "joins" do not fit the structure of showing purpose.

Answer:

A. to join