Receive an array input and output a string
A few stylistic nitpicks: the function body should be indented and there should be a space following the - signs.

getString should be changed to take an array of boolean values, instead of a sparse array of "Y" strings. You can write a separate function to convert your original format to a bool array.

function optionsToBoolArray(array){
    var converted = [];
    for(var i = 0; i &lt; array.length; i++){
        converted[i] = array[i] === "Y";
    }
    return converted;
}


getString is also a undescriptive name for your function. You should change it to something along the lines of optionsToReadableString.

fundMap doesn't need to be an object. Since you are currently using like an array, explicitly make it an array for clarity.

fundString = fundArray + " option"; should be fundString = fundArray[0] + " option"; to avoid implicit conversions for readability.

The code for multiple options can also be simplified by using array methods: 

else {
    fundString = fundArray.slice(0,fundArray.length - 1).join(", ") + " and " + fundArray[fundArray.length - 1] + " options";
}


This also lets you eliminate the else if branch.

You should also extract the console.log out of the function to separate the logic. After doing this, you can eliminate fundString completely by just returning the value from each branch of the if/else.

You should also look into learning ES6 features such as using let instead of var.