A way to improve on the simple monoalphabetic technique is to use different monoalphabetic substitutions as one proceeds through the plaintext message. The general name for this approach is .
A. rail fence cipher
B. cryptanalysis
C. polyalphabetic substitution cipher
D. polyanalysis cipher

Option C i.e., polyalphabetic substitution cipher.

Explanation:

Using that of the various mono-alphabetic replacements as a progresses through all the clear text messages is a method to enhance the basic mono-alphabetic strategy. For such a method the common term is a polyalphabetic substitution cipher.

So, that's why the following option is correct according to the scenario.

solution:

the right option is a

to adding   a new row to a table we   have to do process last table cell and pressing tab.

this is the process to add new row in the cell:

* to add a row below the cell, click insert below in the rows and columns group.

thus this is the required right answer.