I Need answer ASAP

Scientists can detect heat from some kinds of objects in space. This heat is most likely transmitted by which of the following?

Convection only
Radiation only
Convection and conduction
Radiation and conduction

30 points - when can a theory be modified if a new type of technology allows for new observations that raise new questions? a. immediately, while the questions about the theory are being asked b. after new hypotheses related to the theory are tested in experiments c. only after the new observations disprove all parts of the theory d. while scientists begin to think about how the theory could improve