Step 1: Understanding the instruction.
The question asks us to combine the two sentences into one complete sentence without using the conjunctions and, but, or so. Therefore, we must use another grammatical structure such as a participial phrase.
Step 2: Analyzing the options.
(A) uses the conjunction and, which is not allowed according to the instruction.
(B) "Packing up the bundle" changes the meaning slightly because "packing up" suggests arranging or organizing, which is not stated in the original sentence.
(C) "Picking up the bundle, he walked away." correctly uses a present participle phrase to combine the two actions into one sentence without using forbidden conjunctions. It keeps the original meaning intact.
(D) "He walked away by picking up the bundle" changes the meaning because it suggests that walking away happened because of picking up the bundle, which is logically incorrect.
Step 3: Conclusion.
Thus, the correct sentence that combines both statements properly without using and, but, or so is option (C).