Isoelectronic species are the species which have equal no. of electrons. C2H4 has 16 electrons.
a) CN- has 14 e-
b) O2 has 16 e-
c) N2+ has 13 e-
d)O2+ has 15 e-
Hence, C2H4 and O2 has equal no. of e- . So, the answer is opt B

Explanation:

In order to determine the species that is isoelectronic with CH, we need to understand the concept of isoelectronic species and compare the electronic configuration of CH with the given options.

What is Isoelectronicity?
Isoelectronicity refers to the phenomenon where different species have the same number of electrons and similar electronic configurations. These species may belong to different elements or have different chemical formulas, but they share the same number of electrons.

Comparison of CH with the given options:

- Option A: CN-
The electronic configuration of carbon (C) is 1s² 2s² 2p². Hydrogen (H) has one electron in its outermost shell. Therefore, the electronic configuration of CH is 1s² 2s² 2p² 2p¹. On the other hand, the electronic configuration of nitrogen (N) is 1s² 2s² 2p³. So, the electronic configuration of CN- would be 1s² 2s² 2p³ 3s² 3p⁶. Hence, option A is not isoelectronic with CH.

- Option B: O
The electronic configuration of oxygen (O) is 1s² 2s² 2p⁴. Since carbon (C) and oxygen (O) are both in Group 14 of the periodic table, they have the same number of valence electrons. Therefore, the electronic configuration of CH is 1s² 2s² 2p² 2p². The electronic configuration of O is 1s² 2s² 2p⁴, which matches with CH. Hence, option B, O, is isoelectronic with CH.

- Option C: Nd
The electronic configuration of neodymium (Nd) is [Xe] 4f⁴ 6s². The electronic configuration of CH is 1s² 2s² 2p² 2p¹. Since the electronic configurations of Nd and CH are not the same, option C, Nd, is not isoelectronic with CH.

Conclusion:
Among the given options, only option B, O, has the same electronic configuration as CH, making it isoelectronic with CH.