According to Planck, how is energy emitted or absorbed by matter?

Planck's theory introduced the revolutionary concept that energy is not emitted or absorbed continuously, but rather in specific, discrete amounts called "quanta." This idea arose from Planck's attempts to solve the problem of blackbody radiation, where traditional physics could not explain the observed spectrum of emitted radiation. By proposing that energy could only be transferred in these fixed quantities, Planck established that the energy (E) of these quanta is proportional to the frequency (ν) of the radiation, described by the equation E = hν, where h is Planck's constant.

This quantization of energy led to the development of quantum mechanics, fundamentally reshaping our understanding of atomic and subatomic processes. It implies that matter can only exchange energy in specific increments rather than in a smooth, continuous manner. The other options do not align with Planck’s findings, which focus specifically on the discrete nature of energy transfer rather than continuous processes, reactions, or temperature conditions.