The correct answer is option 'A' - electrically.

Explanation:
In this question, we are given that PMDC (Permanent Magnet Direct Current) had no excited machine. To understand the answer, let's break down the question and the options given.

PMDC machines are direct current (DC) machines that use permanent magnets to create the magnetic field required for operation. The magnetic field in these machines is constant and does not require any external excitation source like field windings or electromagnets.

Now, let's analyze the options:

a) electrically: This option suggests that the PMDC machines do not require any electrical excitation for their operation. Since PMDC machines use permanent magnets, they do not need any electrical excitation to create the magnetic field. Therefore, this option is correct.

b) magnetically: This option suggests that the PMDC machines do not require any magnetic excitation for their operation. However, this is incorrect because the permanent magnets used in PMDC machines themselves provide the magnetic field required for operation.

c) none of the mentioned: This option suggests that none of the given options are correct. However, as discussed above, option 'A' - electrically, is the correct answer.

d) least: This option does not provide any relevant information to determine whether PMDC machines require excited machines or not. Therefore, it is not the correct answer.

In conclusion, the correct answer is option 'A' - electrically, as PMDC machines do not require any electrical excitation for their operation.