Which of the following ions has a pseudo-noble-gas electron configuration?
a) ni+
b) fe2+
c) cu+
d) mn2+

ions have a "pseudo-noble-gas" electron configuration.

The ion with the electron configuration is known as Nobel gas. The nature of noble gas is that the cations in this electron configuration are stable.

The Pseudo-noble gas has the electron configuration as:

Since, ion has the same configuration. The example of Nobel gas is, both and are stable compounds. To form only the electron is removed leaving the electronic configuration.

i'm assuming that it's c.) red bank..