Get options in show in shortcode

I’m trying get option in shortcode , how i can make this.

<?php
function chat_bot_conversational() {

	$args = array(
		'id'           => 'principal_bot_response',
		'title'        => 'Principal',
		'object_types' => array( 'options-page' ),
		'admin_menu_hook' => 'network_admin_menu',
		'option_key'   => 'bot_conversation',
		'tab_group'    => 'bot_conversation',
		'tab_title'    => 'Principal',
	);

	if ( version_compare( CMB2_VERSION, '2.4.0' ) ) {
		$args['display_cb'] = 'bots_responses';
	}
	$main_options = new_cmb2_box( $args );
	$group_id = $main_options->add_field( array(
		'id'                => 'questoes_multisite',
		'type'              => 'group',
		'description'       => 'Perguntas ',
		'options'           => array(
			'group_title'   => 'Questão {#}',
			'add_button'    => 'Adicionar Questão',
			'remove_button' => 'Remover Questão',
			'sortable'      => true
		)
	));
	$main_options->add_group_field( $group_id, array(
		'name' => 'Nome do Campo',
		'id'   => 'nome',
		'type' => 'text',
	));
	$main_options->add_group_field( $group_id, array(
		'name' => 'Questão',
		'id'   => 'questao',
		'type' => 'textarea_small',
	));
	$main_options->add_group_field( $group_id, array(
		'name' => 'Grupo',
		'id'   => 'grupo',
		'type' => 'text',
	));
	$main_options->add_group_field( $group_id, array(
		'id'            => 'opcoes_pergunta',
		'name'          => __('Opções ', 'opcoes'),
		'type'          => 'text',
		'sortable'      => true,
		'repeatable'     => true,
	));
}
function myprefix_get_option( $key = '', $default = false ) {
	if ( function_exists( 'cmb2_get_option' ) ) {
		return cmb2_get_option( 'bot_conversation', $key, $default );
	}

	// Fallback to get_option if CMB2 is not loaded yet.
	$opts = get_option( 'bot_conversation', $default );

	$val = $default;

	if ( 'all' == $key ) {
		$val = $opts;
	} elseif ( is_array( $opts ) && array_key_exists( $key, $opts ) && false !== $opts[ $key ] ) {
		$val = $opts[ $key ];
	}

	return $val;
}
add_action( 'cmb2_admin_init', 'chat_bot_conversational' );
function foobar_func( $atts ){
	$bla = myprefix_get_option( 'questoes_multisite');
	print_r($bla);
	return $bla;
}
add_shortcode( 'foobar', 'foobar_func' );