Which of the following visual search tasks would likely be the most difficult for an individual to complete?

• A. Searching for a red circle among green circles
• B. Searching for a blue square among red squares
• C. Searching for a letter 'Q' among letters 'O'
• D. Searching for a triangle among circles

Answer: (C)

Verified step by step guidance

1. Understand the concept of visual search tasks, which involve locating a target item among distractors. The difficulty depends on how similar the target is to the distractors and whether the target differs by a single feature or a conjunction of features.
2. Identify that tasks where the target differs from distractors by a single, simple feature (like color or shape) are usually easier because the target 'pops out' and can be found quickly through parallel processing.
3. Recognize that searching for a red circle among green circles or a blue square among red squares involves a single feature difference (color), making these tasks relatively easy.
4. Note that searching for a triangle among circles involves a shape difference, which is also a single feature difference and typically easier to detect.
5. Understand that searching for a letter 'Q' among letters 'O' is more difficult because the target and distractors share many features (both are circular letters), and the difference is subtle (the small tail on the 'Q'), requiring more focused, serial processing and attention.