In the Context of Iran, the Term "Break-Out" Capability Refers

In the context of Iran, the term "break-out" capability refers to

A) a terrorist organization's ability to begin functioning like a state
B) a terrorist's ability to utilize civilian technology to carry out acts of violent atrocities
C) the ability for a country to cease its economic dependency on oil
D) the ability for a country to set in place the means to rapidly construct a nuclear weapon