Final answer:
To fix the syntax error, encapsulate the object properties in parentheses and return the object from the arrow function.
Step-by-step explanation:
To fix the syntax error in the given code, you need to make two changes:
Here is the corrected code:
const person = (firstName, lastName) => ({ first: firstName, last: lastName });
Now, you can call the function correctly:
person('Jill', 'Wolson');