Spelling mnemonic
Explanation:
mnemonics are different strategies by which we can retain memory and make recalls when necessary. These mnemonics serve to recall the said memory whenever it is required by the person to do so.
In a spelling mnemonic one recalls things by remembering certain aspects of its spelling.
Like in this case, Chad is able to recall the name of the  scientist after he hears the first letter of his name, so it helped him remember the information.
