The warning signs of cancer include all of the following except:

• A. A persistent cough or hoarseness
• B. A sore that does not heal
• C. Unexplained weight loss
• D. Sudden improvement in vision

Answer: (D)

Verified step by step guidance

1. Step 1: Begin by understanding the context of the question. The warning signs of cancer are symptoms that may indicate the presence of cancer and are typically related to abnormal cell growth or tissue damage.
2. Step 2: Review the listed options and identify which ones align with common warning signs of cancer. Persistent cough or hoarseness, a sore that does not heal, and unexplained weight loss are all recognized as potential warning signs of cancer.
3. Step 3: Consider the option 'Sudden improvement in vision.' This is not associated with cancer warning signs. Instead, it may be related to other medical conditions or changes in eye health, but it is not indicative of cancer.
4. Step 4: Compare the options to the general knowledge of cancer symptoms. Cancer warning signs typically involve persistent or unexplained changes in the body, such as weight loss, chronic pain, or non-healing wounds, rather than sudden improvements in bodily functions.
5. Step 5: Conclude that the correct answer is 'Sudden improvement in vision,' as it does not fit the criteria for warning signs of cancer.