Which of the following substances would most likely produce a noticeable change in odour when mixed with vanilla essence?

To determine which substances would most likely produce a noticeable change in odor when mixed with vanilla essence, we need to consider the properties and aromatic compounds in the substances in question.

Substances that have strong or distinct odors that interact with the sweet, creamy notes of vanilla are likely candidates. For example:

1. Citrus Fruits (like lemon or orange zest) - These contain essential oils that have strong, fresh scents and may create a noticeable contrast to vanilla.
2. Spices (like cinnamon or nutmeg) - These spices have robust, aromatic profiles that can blend or clash with the vanilla aroma.
3. Herbs (like mint or basil) - Fresh herbs might alter the smell because their chlorophylls and oils have unique fragrances.

However, it is important to be specific about the substances provided in the question for a more accurate answer. If the question lists specific substances, I can give a more precise response based on that information.