To alter just one character in a stringbuilder, you can use the method, which allows you to change a character at a specified position within a stringbuilder object.
a.
insert()
b.
setcharat()
c.
append()
d.
charat()

setCharAt()

Explanation:

StringBuilder is a dynamic object that allow to create the string with no size restriction.

To answer the question, let discuss each option.

Option a: insert()

insert function is used to insert the element at the specific location but it does not change the rest of the character.

Option b: setCharAt()

it is used to change the value at specific location, it takes two argument location and character.

Option c: append()

it is used to connect the two string but it does not change the rest of the character.

Option c: charAt()

it is used to get the character at specific location. it does not allow the change.

Therefore, option b is correct option.

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