Tom is writing a software program that calculates the sales tax for online orders placed from various jurisdictions. The application includes a user-defined field that allows the entry of the total sale amount. Tom would like to ensure that the data entered in this field is a properly formatted dollar amount. What technique should he use?

a. Limit check

b. Fail open

c. Fail secure

d. Input validation

The answer is "Option d".

Explanation:

We use the input validation process to check that inserted data is properly formatted or not. This process provides validation in data that is inserted by a client. When an unauthorized user trying to defend code so, there will arise some error and it is difficult to detect programs To solve this problem we must verify and validate all entries submitted into a program. and other options are not correct that can be described as follows:

In option a, It is used to check that the inserted value limit is not higher or lower. In option b, This process is used when there is a loss of signals. This process opens a system or program in warning mode. In option c, This process starts when a power failure occurs. The default state of this process is locked.