To answer this question, the user needs to have some basic understanding of Packed-Decimal and its performance considerations.

Packed-Decimal is a data format used in computer systems to store decimal numbers efficiently. It stores two digits in a single byte, allowing for more efficient storage of decimal values. In terms of performance, the number of digits used in Packed-Decimal can affect the speed of operations involving these values.

Now, let's go through each option and determine which statement is true:

A. (1) Using an odd number of digits is 10% to 30% slower than using an even number of digits - This statement is false. According to performance benchmarks, using an odd number of digits in Packed-Decimal is actually faster than using an even number of digits.

B. (2) Using an even number of digits is 10% to 30% faster than using an odd number of digits - This statement is false. As mentioned, using an odd number of digits is actually faster than using an even number of digits.

C. (3) Using an odd number of digits is 5% to 20% slower than using an even number of digits - This statement is also false. Using an odd number of digits is faster, not slower, than using an even number of digits.

D. (4) Using an odd number of digits is 5% to 20% faster than using an even number of digits - This statement is true. According to performance benchmarks, using an odd number of digits in Packed-Decimal is 5% to 20% faster than using an even number of digits.

Therefore, the correct answer to this question is:

The Answer is: D. (4) Using an odd number of digits is 5% to 20% faster than using an even number of digits.