Plugin auto-generating more than a dozen thumbnails

I discovered using the Regenerate Thumbnails plugin that this plugin is automatically generating more than a dozen thumbnails on each image upload..

newspack-article-block-landscape-large: 1200×900 pixels (cropped to fit)

newspack-article-block-portrait-large: 900×1200 pixels (cropped to fit)

newspack-article-block-square-large: 1200×1200 pixels (cropped to fit)

newspack-article-block-landscape-medium: 800×600 pixels (cropped to fit)

newspack-article-block-portrait-medium: 600×800 pixels (cropped to fit)

newspack-article-block-square-medium: 800×800 pixels (cropped to fit)

newspack-article-block-landscape-small: 400×300 pixels (cropped to fit)

newspack-article-block-portrait-small: 300×400 pixels (cropped to fit)

newspack-article-block-square-small: 400×400 pixels (cropped to fit)

newspack-article-block-landscape-tiny: 200×150 pixels (cropped to fit)

newspack-article-block-portrait-tiny: 150×200 pixels (cropped to fit)

newspack-article-block-square-tiny: 200×200 pixels (cropped to fit)

newspack-article-block-uncropped: 1200×9999 pixels (proportionally resized to fit inside dimensions)

How do I turn this setting off? Right now I’m having to use ThumbPress to manually deactivate them.. But I don’t want to keep a separate plugin just to solve this issue..

Thanks