All natural processes are

Explanation:

• A chemical process in which the standard change in free energy is positive and energy is received from the outside is known as a non-spontaneous process.
• The endothermic process takes energy in the form of heat from the environment.
• An exothermic process, on the other hand, releases energy into the system's surroundings.
• Processes that do not use energy from any external source are known as spontaneous processes.
• Natural processes do not require any external energy, so they are spontaneous 

Final answer:

Hence, the correct option A, i.e. Spontaneous.