Expand the compressed IPv6 address FF02::130F:5 into its full eight group representation with all 16-bit sections shown.

Introduction / Context:
IPv6 addresses are often written in a compressed format to save space, using rules that allow removal of leading zeros and one sequence of all zero groups. For troubleshooting, exams, and configuration tasks, you must be able to expand a compressed IPv6 address back into its full eight 16 bit group representation.

Given Data / Assumptions:

• The compressed IPv6 address is FF02::130F:5.
• An IPv6 address always consists of eight 16 bit groups.
• The double colon (::) stands for one or more consecutive groups of all zeros.
• We must determine exactly how many zero groups are compressed in this example.

Concept / Approach:
To expand an address with ::, count how many groups are explicitly shown, then calculate how many groups of 0000 must be inserted to reach a total of eight groups. The part before :: and the part after :: together determine this count. All omitted groups are replaced by 0000, and leading zeros in each group are restored so that each group has four hexadecimal digits.

Step-by-Step Solution:
1. Start with the compressed address FF02::130F:5.2. Identify the groups present before the double colon: FF02 represents one 16 bit group.3. Identify the groups present after the double colon: 130F and 5 represent two more groups, with 5 implying the group 0005 when fully written.4. Count the explicitly shown groups: 1 group before :: and 2 groups after ::, for a total of 3 groups.5. An IPv6 address must have 8 groups, so 8 - 3 = 5 groups are missing and are therefore all zeros.6. Insert five consecutive 0000 groups between FF02 and 130F, giving FF02:0000:0000:0000:0000:0000:130F:0005 as the full expanded address.

Verification / Alternative check:
After expansion, verify that you still have exactly eight groups and that reapplying compression rules could produce the original form. Compressing the full address by replacing the longest sequence of zero groups with :: and removing leading zeros yields FF02::130F:5 again, confirming that the expansion is correct.

Why Other Options Are Wrong:
Option B incorrectly places 130F in the seventh position by inserting only four zero groups, resulting in a different address structure. Option C and option D place 130F earlier in the address and leave the wrong number of zero groups between nonzero segments. Any such misplacement alters the binary value of the address and no longer matches the original compressed representation.

Common Pitfalls:
A frequent error is to insert the wrong number of zero groups because the student forgets that the total must always be eight groups. Another mistake is to distribute zero groups on both sides of the double colon instead of keeping them as a single contiguous block. Carefully counting existing groups and performing simple subtraction is the safest method to expand compressed IPv6 addresses accurately.

Final Answer:
FF02:0000:0000:0000:0000:0000:130F:0005