Why do astronomers find it difficult to locate extrasolar planets with telescopes? a. from our distance, they are very close to the stars they orbit. b. planets wobble due to the gravity of the stars they orbit. c. planets only emit invisible wavelengths of light.

The answer is; A

The bright light from the stats they orbit makes its difficult for the exoplanets to be viewed by a telescope because the planets are much dimmer than the stars. Unique telescopes (The Transiting Exoplanet Survey Satellite (TESS) & Kepler telescope) are able to search for these exoplanets by utilizing the phenomenon where the stars tend to dim after regular intervals of time hence signifying a planet orbiting the star.  Depending on the dimming, the size of the planet can also be deduced.

the following sets of characteristics describe what we know about the outer plants is c. rocky surface, closet to the sun and larger in size