I've Searched The Web So Much But For Some Reason, My Code = No Work;

My JavaScript:

let a = document.getElementById("a");
let b = document.getElementById("b");
let c = document.getElementById("c");
let button = document.getElementById("button");

button.onclick = function() {    
    var info = {"a": a.value, "b": b.value, "c": c.value};
    console.log(info.a + info.b + info.c);
}

Everything Except The C One Works, Which Is A Dropdown(A And B Are Textboxes).

HTML:

<button type = "button" id = "button">Button</button>
<input type = "text" id = "a">
<br><br>
    
<input type = "text" id = "b">        
<br><br>

<select name = "c" class = "c">
<option value = "c1" class = "c" selected>c1</option>
<option value = "c2" class = "c">c2</option>
<option value = "c3" class = "c">c3</option>