Question

the lab worker is ____________ the temperature of an ostrich egg to estimate its time until hatching. adapt; monitor; simulate; -ed; -ing; -ion

Explanation:

The context implies observing the egg's temperature. "Monitor" means to observe and check something over time, which fits the situation of observing the temperature to estimate hatching time. The present - participle form "monitoring" is used to complete the sentence as it shows an ongoing action.

Answer:

monitoring