Final answer:
The timing of the pain starting 2 hours ago is part of the T (Time) component of the OPQRST history.
Step-by-step explanation:
The answer to your question is 1) T (Time). In the context of the OPQRST history, T stands for the timing of symptoms. Learning that the patient's pain started 2 hours ago is part of the timing information. This can be an important aspect of the patient's medical history as it helps healthcare professionals understand the progression and duration of symptoms.