When an Element Has Z=26 and 29 Neutrons, What Element ${ }_{29}^{26} \mathrm{Cu}$

Multiple Choice

When an element has Z=26 and 29 neutrons, what element and isotope is this?

A) ${ }_{29}^{26} \mathrm{Cu}$
B) ${ }_{29}^{55} \mathrm{Cu}$
C) ${ }_{26}^{29} \mathrm{Fe}$
D) ${ }_{26}^{55} \mathrm{Fe}$