Among the following elements have same no. of neutrons is/are

The elements having same number of neutrons are called isotones.

${}_7{}^{15}\mathrm{N}, {}_6{}^{14}\mathrm{C}$

No. of neutrons=8

${}_7{}^{15}\mathrm{N}, {}_8{}^{16}\mathrm{O}$

No. of neutrons=8.