Suppose Markus offers to sell Zara his surfboard for $$200.$ Zara responds, "I'll look at it on the weekend, and if I like it$,$ I'll pay you." At this point, Zara has not committed to doing anything. The law considers this a$($n$)\_\_\_\_\_\_\_\_$blank.

multiple choice

illusory promise

promissory estoppels

preexisting duty

valid consideration

past consideration