Which of the following could lead to false indications on a test specimen during penetrant testing?

During penetrant testing, the presence of penetrating liquids on the test table or inspector's hands can lead to false indications on the test specimen. If the inspector inadvertently transfers penetrant from their hands or the table to the specimen, it can create additional unwanted indications that may mimic actual defects or flaws. This contamination can obscure true results and lead to misinterpretation of the test outcomes.

Other factors, while they may affect the testing process, do not have the same direct impact on the integrity of the indications. For instance, excessive lighting can enhance visibility, making it easier to detect real indications rather than causing false ones. Water contamination in the testing area might affect the effectiveness of the penetrant or the wash but is not directly responsible for introducing false indications. Using multiple developers could lead to variations in appearance or clarity but is more about the outcomes rather than misleading indications that could arise from surface contamination.