Final answer:
Without access to the specific edition of the World Wide Menu, it's not possible to provide the mandatory ingredient for omelets and scrambled eggs as stated in the preface. The inclusion of ingredients like herbs, cheese, cooking oil, and salt and pepper typically depends on individual recipes and personal preferences.
Step-by-step explanation:
It seems that there may be a misunderstanding or an error in the question, as the World Wide Menu (WWM) is not a widely recognized or standard text for which a generic answer would be available. Typically, the preparation of omelets and scrambled eggs does not have any mandatory ingredients beyond eggs themselves; additional ingredients like fresh herbs, cheese, cooking oil, and salt and pepper are based on individual recipes and personal preference. To locate the specific answer to this question, one would need to have access to the specific edition of the WWM text mentioned. However, without that text, I am unable to provide a definitive answer. I recommend revisiting the preface of the World Wide Menu referenced to find the mandatory ingredient for omelets and scrambled eggs as specified there.