Question

Proxy data:

provide climate data representing times when instruments were not available to measure them.
can only extend the temperature record back an additional 500 years.
come quality-controlled instrument records.
are difficult to find because they occur only in very limited areas.

Answer 1

Answer: provide climate data representing times when instruments were not available to measure them.

Step-by-step explanation:

Proxy data provides climate data representing times when instruments were not available to measure them.