In American culture the word "modesty", used by itself, can have two references.
It can refer to an individual's dress code. A dress code in which the individual does not reveal their body or the clothing is simple and plain.
EXAMPLE 1: His skimpy swim suit showed that he had no modesty.
EXAMPLE 2: The modesty of her dress enhanced her beauty.
The second reference to modesty can be about an individual's character. It would mean "humble" or "humility".
EXAMPLE: All of his actions we surrounded with modesty and grace.
In your thesis statement you need to connect the word "modesty" to one of these concepts. As it stands, I have to assume which one you mean. If I choose the wrong reference, I would be responding to something other than what you intended.