Which HTML should you use?

You are developing a customer web form that includes the following HTML input field.

<input id=”txtValue”/>
If a customer enters a value in the input field, then it must be a numeric value.
You need to add validation to the input field.
Which HTML should you use?

A.
<input id=”txtValue” type-“text” pattern=”/#” />

B.
<input id=”txtValue” type=”number” />

C.
<input id=”txtVa!ue” type=”integer” />

D.
<input id=”txtValue” type=”text” required=”required”/>

Explanation:

Reference:
http://www.w3schools.com/html/html5_form_input_types.asp