Which term best describes the temperature and weather conditions of an organism’s environment?

The most accurate term is just "environment" or "weather". I'll explain below.

The answer that your teacher is probably looking for is "climate".

People often confuse climate vs weather. Based on this question, it's either sort of a trick or the person asking the question may not know the difference.

The difference between climate and weather is just a measure of time. Conditions of our atmosphere over a short period of time is how we define weather; examples are snow or sun, or hot or cold. How our atmosphere behaves over long periods of time is what we define as a climate.

So, when we talk about climate change, we're not talking about the weather or the temperature on a given day...We're talking about long-term averages of daily weather.

This question asks about temperature and weather conditions, which would be defined just as "weather".

Hope this helps!