Bootstrap Multiselect plugin - how to get values in php

JavaScript
1

I’m using the Bootstrap Multiselect plugin and I can’t figure out how to get the values in php.
Here is my html


    <select class="form-control" name="product" multiple>
     <option value="a">a</option>
     <option value="b">b</option>
     <option value="c">c</option>
    </select>

here is the entire jquery block


    $(document).ready(function() {

    $('.home1')
      .find('[name="product"]')
        .multiselect({
         // Re-validate the multiselect field when it is changed
          onChange: function(element, checked) {
            $('#home1')
                .data('bootstrapValidator')                 // Get plugin instance
                .updateStatus('product', 'NOT_VALIDATED')  // Update field status
                .validateField('product');                 // and re-validate it
        }
      })
      .end()
      .bootstrapValidator({
      excluded: ':disabled',
    message: 'This value is not valid',
    live: 'disabled',
    feedbackIcons: {
        valid: 'glyphicon glyphicon-ok',
        invalid: 'glyphicon glyphicon-remove',
        validating: 'glyphicon glyphicon-refresh'
    },
    submitHandler: function(validator, form, submitButton) {

        $.ajax({
          type: "POST",
          url: "process-step1.php",
          data: $('.home1').serialize(),
          success: function(msg){
              document.location.href = 'form.php';
          },
          error: function(){
            alert("error");
          }
        });//close ajax
    },
    fields: {
        product: {
            validators: {
                callback: {
                    message: 'Please choose 1-5 products',
                    callback: function(value, validator) {
                        // Get the selected options
                        var options = validator.getFieldElements('product').val();
                        return (options != null && options.length >= 1 && options.length <= 5);
                    }
                }
            }
        }// product

    } // end field
    });// bootstrapValidator

    }); //ready(function

In the javascript I can get the values by with this…


     var options = validator.getFieldElements('product').val();
     alert(options);

But how do I then send it to php in my ajax function


    $.ajax({
       type: "POST",
         url: "process-step1.php",
          data: $('.home1').serialize(),
          success: function(msg){
             document.location.href = 'form.php';

          },

also once in php how do I get each value?