The human resource chief said that the company will not ____________ on investing in people and has ____________ spending on employee needs in order to ____________ them and provide them with a sense of stability and certainty.

For the first blank, we need a verb that implies that the company will not reduce or give up on investing in people. For the second blank, a past-tense verb is required that suggests a favourable action regarding spending. For the third blank, we want a verb that means to support, or reassure employees.

Compromise is the best choice for the first blank, prioritise is the best choice for the second blank, and both reassure and empower can be good choices for the third blank. 

Hence, option C is the best choice.