In a certain symbol code, the word RAT is written as "@$&" and the word HEAD is written as "%*$#". Using the same letter-to-symbol substitution, how will the word THREAD be written in that code?

Introduction / Context:
This is a straightforward substitution coding problem where each letter is replaced by a unique symbol. You are told how RAT and HEAD are coded, and you must determine the code for THREAD. Because THREAD is built from the same letters R, H, E, A, D, we can reuse the mapping without any new deductions. Such questions are often asked to test whether you can build and apply a consistent substitution table for letters and symbols.

Given Data / Assumptions:

• RAT → "@$&".
• HEAD → "%*$#".
• Letter-to-symbol mapping is consistent in every word.
• We must code THREAD, which uses letters T, H, R, E, A, D.

Concept / Approach:
We first identify the symbol assigned to each letter using the given examples. From RAT, we recover codes for R, A, and T. From HEAD, we obtain codes for H, E, A, and D and check consistency where letters repeat. Then we write THREAD in order and replace each letter with its corresponding symbol. This is a direct one-to-one substitution with no rearrangement or arithmetic involved.

Step-by-Step Solution:
Step 1: From RAT → "@$&", map R → @, A → $, T → &. Step 2: From HEAD → "%*$#", map H → %, E → *, A → $, D → #. Step 3: Check consistency: A → $ appears in both words, confirming correctness. Step 4: Now list letters of THREAD in order: T, H, R, E, A, D. Step 5: Substitute each letter using the mapping: T → & H → % R → @ E → * A → $ D → # Step 6: Combine these symbols: & % @ * $ #, giving &%@*$#.

Verification / Alternative check:
To verify, substitute back: &%@*$# → T H R E A D. Since each symbol returns to a unique letter and we can also reconstruct RAT and HEAD from "@$&" and "%*$#", we know the mapping is consistent across all words. There is no rearrangement or extra symbol, so &%@*$# is an exact encoding of THREAD under the given scheme.

Why Other Options Are Wrong:
Option A (#$*@%&) jumbles the symbols in the wrong order; it would decode as D A E R H T, not THREAD. Option B (@#%$*&) also misorders the symbols. Option D (&*$%#@) changes the order of symbols so the letter sequence would be T E A H D R. Option E (@$%*#&) does not follow the correct letter order of THREAD. Only Option C matches the exact sequence T, H, R, E, A, D mapped symbol by symbol, so only it is valid.

Common Pitfalls:
The most frequent mistake is to lose track of the letter order in the target word or to copy symbols incorrectly. Another issue is assuming some rearrangement of letters is happening when it is purely a substitution. Always write out a mapping table and then carefully substitute, checking each position. Consistent attention to detail is enough to avoid errors in this type of problem.

Final Answer:
Thus, the word THREAD is written as &%@*$# in the given symbol code.