Displaying all pages which comes under a category id

Use this code ,

<?php
$args = array(
    'posts_per_page' => -1,
    'offset' => 1,
    'category' => 4,
    'numberposts' => -1
);
$pages = get_pages($args);
$i = 1; 
    foreach ($pages as $page) {
        if ($i == 1) { ?>
            <div class="carousel-item active" style="background-image: url('<?php echo get_bloginfo('template_url'); ?>/img/intro-carousel/1.jpg');">
                <div class="carousel-container">
                    <div class="carousel-content">
                        <?php $image = wp_get_attachment_image_src(get_post_thumbnail_id($page->ID), 'optional-size'); ?>
                        <h2><?php echo $page->post_title; ?></h2>
                        <p>
                            <?php echo strip_tags(get_the_excerpt()); ?>
                            <span>Convert Visitors Into Customers And Generate More Sales</span>
                        </p>
                            <a href="#about" class="btn-get-started scrollto">
                                <img src="<?php echo $image[0]; ?>" alt="arrow"/>
                            </a>
                    </div>
                </div>
            </div>
        <?php } else { ?>
            <div class="carousel-item" style="background-image: url('<?php echo get_bloginfo('template_url'); ?>/img/intro-carousel/1.jpg');">
                <div class="carousel-container">
                    <div class="carousel-content">
                        <?php $image = wp_get_attachment_image_src(get_post_thumbnail_id($page->ID), 'optional-size'); ?>
                            <h2><?php echo $page->post_title; ?></h2>
                            <p>
                                <?php echo strip_tags(get_the_excerpt()); ?>
                                <span>Convert Visitors Into Customers And Generate More Sales</span>
                            </p>
                            <a href="#about" class="btn-get-started scrollto">
                                <img src="<?php echo $image[0]; ?>" alt="arrow"/>
                            </a>
                    </div>
                </div>
            </div>
        <?php }
        $i++;
    }
    wp_reset_query();
?>