What makes phenolphthalein a less sensitive option in tests?

Phenolphthalein is a pH indicator commonly used in forensic testing, particularly in the presence of blood. While it can react to certain substances, it is less sensitive to a broader range of potential indicators. This means that its reaction is specifically dependent on the pH level of the environment and the presence of certain substances, primarily detecting the alkaline conditions created by blood due to the hemoglobin present.

In contrast, other indicators may have a wider range of sensitivity to various substances, allowing them to detect a broader spectrum of reactions and chemical compounds. Thus, phenolphthalein’s limited sensitivity to a variety of compounds makes it less optimal in certain testing scenarios where a more versatile indicator is preferable.

The other options pertain to specific limitations or characteristics of phenolphthalein. For instance, while it may encounter challenges with complex procedures or light sensitivity, these factors are not as central to its overall sensitivity as its chemical behavior and specificity.